The Biostatistical, Data Management and Clinical Core of the Oral Cancer Research Center. (Center) will offer a wide range of methodological, technical and analytical expertise to each of the individual projects. It will also be instrumental in developing a common language for data interpretation which will facilitate the exchange of results between studies and the formulation of common concepts. It will be responsible for experimental design, data management and statistical analysis, and will provide Center staff with the resources needed to enhance research programs through the application of epidemiology, sampling, biostatistics and related support methodologies. In addition, this core will identify appropriate clinical populations and facilitate access to these populations for the purposes of data collection related to the activities of the Center. The services provided by this core will be used by all four Research Projects and Pilot Projects. The availability of standardized procedures for data reporting and analysis will enable each investigator to extract as much information as possible from the collected data and facilitate the integration of individual projects as well as communication between investigators in the various Research Projects. The operation of a centralized data bank will allow additional comparisons of various study groups across Projects and thus derive more information from the Program Projects as a whole than from the sum of each of its components. This core will strengthen the planning, implementation and conduct of oral cancer research through biostatistician/investigator interactions.